This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Biparental HLA Haplotype Disparate T-cell Depleted Transplants for Patients Lacking an HLACompatible Donor (NCT01598025), a non-randomized na study. The primary outcome is Efficacy of HLA-haploidentical Biparental T-cell Depleted CD34+ Peripheral Blood Stem Cell Transplants.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01598025 |
| Phase | NA |
| Condition | Acute Leukemia, Chronic Leukemia, Myelodysplastic Syndrome |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 3 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Memorial Sloan Kettering Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned patients lacking an HLA-compatible donor who were candidates for a transplant. Conditions named in the registry record include acute leukemia, chronic leukemia, myelodysplastic syndrome, and Non-Hodgkins Lymphoma. The record describes an intended population, but does not report enough detail to characterize the enrolled participants or their clinical circumstances.
Intervention
The study tested a transplant using blood from two donors, each sharing one half of the recipient’s HLA type, with both donors’ blood transplanted at the same time. The intervention list includes allogeneic hematopoietic stem cell transplantation and peripheral blood stem cell transplantation, along with conditioning treatments and laboratory biomarker analysis. The record describes two regimens, but the descriptions are incomplete.
Comparator
This was a non-randomized, parallel study with no masking. The registry record does not identify a randomized control group or a like-for-like comparison. It therefore does not support interpreting differences between any groups as the effect of the transplant strategy. The record also does not report an HLA-matched donor group as a comparator.
Primary question
The stated primary objective was to evaluate the efficacy of HLA-haploidentical biparental T-cell depleted CD34+ peripheral blood stem cell transplants. At 1 year, efficacy was to be assessed through transplant-related mortality, overall and disease-free survival, engraftment and hematopoietic reconstitution, graft failure, graft-versus-host disease, and opportunistic infections. The registry record says the primary objectives could not be analyzed.
3. Trial Design
The registry record describes NCT01598025 as a non-randomized, parallel study with no masking and a phase recorded as NA. Memorial Sloan Kettering Cancer Center is identified as the sponsor. The record lists the study start as 2012-05-02, primary completion as 2017-10-16, and status as terminated. Enrollment was 3.
The study addressed transplantation for patients without an HLA-compatible donor. Its brief summary describes a strategy using blood from two donors, each sharing one half of the recipient’s HLA type, transplanted at the same time. The intervention list includes total-body irradiation, thiotepa, fludarabine phosphate, melphalan, anti-thymocyte globulin, allogeneic hematopoietic stem cell transplantation, peripheral blood stem cell transplantation, and laboratory biomarker analysis. These listed interventions do not establish which treatments each participant received.
Two regimen descriptions appear in the record. The first description is truncated, and the second is also incomplete. One states that it is intended for patients with non-malignant, life-threatening diseases and patients with hematologic malignancies, extensive prior therapy, and comorbidities who are unable to receive TBI. The incomplete descriptions do not allow a complete reconstruction of treatment assignment or exposure. The adverse-event group is labeled Regimen 2, but that label alone does not show how every participant was assigned or treated.
Because allocation was non-randomized, the study design does not provide the protection against confounding that random allocation can offer. No masking also means that outcome assessment was not described as blinded. These design features matter when interpreting observed outcomes, but they do not by themselves establish bias in a particular direction. The registry record does not report a control comparison suitable for estimating a causal treatment effect. It also states that, because of small accrual and patient course following treatment, the primary objectives could not be analyzed.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | REGIMEN 1 | Regimen 2 |
|---|---|---|
| STARTED | 0 | 3 |
| COMPLETED | 0 | 0 |
| NOT COMPLETED | 0 | 3 |
Analysis population for the primary outcome, as defined in the registry: Due to the small accrual on study, as well as patient course following treatment on study, the primary objectives of this study were not able to be analyzed.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Zero participants were enrolled to Regimen 1
| Characteristic | Unit | REGIMEN 1 | Regimen 2 | Total |
|---|---|---|---|---|
| Participants analysed | 0 | 3 | 3 | |
| Age, Continuous | years | — | 12 (11 to 17) | 12 (11 to 17) |
| Sex: Female, Male: Female | Participants | 0 | 1 | 1 |
| Sex: Female, Male: Male | Participants | 0 | 2 | 2 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 0 | 3 | 3 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 2 | 2 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): White | Participants | 0 | 1 | 1 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | Participants | 0 | 3 | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Efficacy of HLA-haploidentical Biparental T-cell Depleted CD34+ Peripheral Blood Stem Cell Transplants, measured over 1 year.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary objective was efficacy of HLA-haploidentical biparental T-cell depleted CD34+ peripheral blood stem cell transplants, with a timeframe of 1 year. Rather than one outcome, the objective included several domains: transplant-related mortality, overall survival and disease-free survival; engraftment and hematopoietic reconstitution, including graft failure; acute and chronic graft-versus-host disease (GVHD); and opportunistic infections developing following engraftment. The registry record does not provide numerical results for these primary outcomes.
In general, this collection of outcomes is intended to describe both whether recipients remain alive and free of disease and whether the transplanted cells establish blood-forming function, while also tracking complications. These are distinct measures: an outcome in one domain does not substitute for results in another. For example, survival information alone would not characterize engraftment or GVHD. The registry record does not provide operational definitions for each measure, such as how disease-free survival or graft failure was defined, or how events were adjudicated.
The stated timeframe gives a horizon for the planned assessment, not proof that every participant had complete follow-up to that point. The record says the primary objectives could not be analyzed, so the planned measures cannot be treated as reported estimates of efficacy. Specific endpoint definitions, analysis populations, and primary outcome results are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive fact is that enrollment was 3 and the registry record says the primary objectives were not able to be analyzed. Although the primary objective names outcomes at 1 year, no primary outcome estimates, confidence intervals, hypothesis tests, or analysis results are reported in the record. Consequently, the posted information does not quantify transplant-related mortality, overall survival, disease-free survival, engraftment, graft failure, GVHD, or opportunistic infections as primary outcomes.
The adverse-event information is a separate descriptive record. For the group labeled Regimen 2, 3 participants were at risk for serious adverse events and 2 were recorded as affected; 3 were at risk for other adverse events and 3 were recorded as affected. The record also lists 3 deaths. It does not provide the information needed to attribute those deaths or events to the transplant, a specific component of treatment, the underlying disease, or other clinical circumstances. The adverse-event figures should therefore be read as reported counts, not as estimates of causal risk.
The serious-event terms listed include bronchopulmonary hemorrhage and hypoxia, each reported as 66.7%, and acidosis, hypotension, multi-organ failure, and myelitis, each reported as 33.3%. These percentages describe registry entries, but the record does not explain whether terms overlap in the same participants, whether they represent episodes or people, or the observation period used. They should not be added together or interpreted as separate patient shares.
There is no randomized comparison, and the registry record does not report a suitable control group. Thus, even if descriptive outcomes were available, comparisons between treatment groups would not automatically establish that treatment caused differences. Here the primary objectives were not analyzed, so there is no reported primary treatment-effect estimate to interpret. The record does not report p-values or confidence intervals for those outcomes.
In general, a confidence interval communicates the range of values compatible with an estimate under the statistical model and assumptions used. Its absence means the precision of a primary outcome estimate cannot be assessed from the registry record. It does not mean the true effect is zero or that the study established equivalence. The small enrollment and absence of analyzable primary results sharply limit what can be concluded about the stated clinical question.
9. Statistical Methods Explained
The study is recorded as non-randomized, parallel, and unmasked. Those labels describe key design features. In general, a parallel design assigns participants to different treatment groups that proceed alongside one another; non-randomized allocation means treatment assignment is not described as being determined by chance. With non-random allocation, baseline differences between groups can complicate comparisons. Masking is recorded as none, so the record does not describe blinding of participants or investigators. The registry record does not report additional details about allocation procedures or outcome assessment.
What do the primary outcomes represent?
The primary objective groups several outcomes under efficacy, rather than reporting a single numerical endpoint. Transplant-related mortality, overall survival, and disease-free survival are listed for 1 year post transplant. Engraftment and hematopoietic reconstitution, graft failure, acute and chronic GVHD, and opportunistic infections are also included. In general, such outcomes address different aspects of post-transplant course and should be interpreted separately unless a prespecified composite is defined. The record does not report a composite definition, detailed measurement rules, or numerical estimates for these outcomes.
What can be said about statistical testing?
The registry record reports no analyses. It does not report estimates, standard errors, confidence intervals, p-values, or the statistical procedures used for the primary objectives. Accordingly, there is no posted inferential result from which to assess the magnitude or precision of a primary treatment effect. The absence of an analysis result should not be read as a finding of no effect; it means that the stated primary objectives were not analyzed in the registry record.
In general, statistical inference uses an estimate and its uncertainty to distinguish the observed data from the range of effects that remain plausible under a model. A p-value, when reported, addresses how unusual data would be under a specified null model; it does not measure clinical importance or prove causation. A confidence interval communicates uncertainty around an estimate under its model assumptions. Neither is reported for the primary outcomes here, so these concepts cannot be applied to a numerical primary result.
How should the planning illustrations be understood?
The registry record describes planning illustrations based on an observed effect, with two-sided significance level 0.05, equal allocation between two arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect. These illustrations are not the study’s own design justification, and their sample sizes are planning quantities rather than actual study findings. They are not observed power. The record does not report the protocol’s sample-size justification, and the primary objectives could not be analyzed. Therefore, these planning assumptions do not repair the lack of an analyzable primary result.
In general, a sample-size calculation is conditional on assumptions about the outcome, effect size, variability, allocation, and statistical test. If those assumptions differ from the study’s actual circumstances, the planned sample size may not offer the expected precision. Over-dispersion is a general concern when observed variability exceeds the model’s assumed variability; in that situation, standard errors from a simpler model may be too small and uncertainty may be understated. The registry record does not report whether over-dispersion was assessed or relevant to any outcome.
What do the adverse-event counts establish?
The record gives at-risk and affected counts for serious and other adverse events in the Regimen 2 group, and it lists deaths. These are descriptive counts. A rate or comparison requires a clearly specified observation window and denominator definition, and a causal interpretation requires further design and analysis support. The registry record does not report those details or an inferential safety analysis. The serious-event term percentages are reported as percentages, but definitions of event counting and overlap are not reported.
Overall, the design labels and reported counts allow a limited description of how the trial was structured and what adverse-event entries were posted. They do not provide an estimate of comparative efficacy or establish that the transplant strategy caused a particular outcome. The record does not report a statistical analysis plan, interim analyses, adjustment methods, or detailed outcome definitions.
10. Multiplicity, Missing Data and Analysis Populations
The primary objective includes several outcome domains: transplant-related mortality, overall survival, disease-free survival, engraftment and hematopoietic reconstitution, graft failure, acute and chronic GVHD, and opportunistic infections. Evaluating multiple outcomes can raise multiplicity concerns. In general, if several statistical hypotheses are tested, the chance of at least one apparently unusual result can increase unless the analysis plan accounts for the number and structure of the tests. The registry record does not report a multiplicity strategy, endpoint hierarchy, or adjusted results.
The record states that no analyses were reported and that the primary objectives could not be analyzed. It therefore does not report outcome-specific estimates or tests that could be assessed for multiplicity. A missing multiplicity plan should not be interpreted as evidence that an adjustment was either required or unnecessary; the actual analysis procedures are not reported in the registry record.
Missing-data handling is also not reported in the registry record. The record does not describe completeness of follow-up, reasons for missing measurements, censoring rules, imputation, or sensitivity analyses. The stated primary timeframe is 1 year, but that does not establish that every participant contributed a complete 1-year outcome. General statistical practice distinguishes missing outcome data from an observed absence of an event; without follow-up and missingness details, the two cannot be equated.
The analysis populations are not reported in the registry record. It does not state whether the intended analysis was based on all enrolled participants, participants who received a transplant, or another defined population. In general, an analysis population should be defined in relation to allocation, treatment received, and outcome availability. With enrollment of 3 and no analyzable primary objectives, the posted record cannot establish which participants contributed to any primary endpoint analysis.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Regimen 2 | 2 | 3 | 66.7% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Regimen 2 | 3 of 3 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Regimen 2 | 3 of 3 |
Most frequent serious adverse event terms
| Event term | Organ system | Regimen 2 |
|---|---|---|
| Bronchopulmonary hemorrhage | Respiratory, thoracic and mediastinal disorders | 2 of 3 |
| Hypoxia | Reproductive system and breast disorders | 2 of 3 |
| Acidosis | Metabolism and nutrition disorders | 1 of 3 |
| Hypotension | Vascular disorders | 1 of 3 |
| Multi-organ failure | General disorders | 1 of 3 |
| Myelitis | Infections and infestations | 1 of 3 |
| Nervous system disorders - Other, specify | Nervous system disorders | 1 of 3 |
| Pancreatitis | Gastrointestinal disorders | 1 of 3 |
| Renal and urinary disorders - Other, specify | Renal and urinary disorders | 1 of 3 |
| Sinus tachycardia | Cardiac disorders | 1 of 3 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Regimen 2 |
|---|---|---|
| Lymphocyte count decreased | Investigations | 3 of 3 |
| Platelet count decreased | Investigations | 3 of 3 |
| White blood cell decreased | Investigations | 3 of 3 |
| Anemia | Blood and lymphatic system disorders | 2 of 3 |
| Hypokalemia | Metabolism and nutrition disorders | 2 of 3 |
| Neutrophil count decreased | Investigations | 2 of 3 |
| Activated partial thromboplastin time prolonged | Investigations | 1 of 3 |
| Hyperglycemia | Metabolism and nutrition disorders | 1 of 3 |
| Hyperkalemia | Metabolism and nutrition disorders | 1 of 3 |
| Hypocalcemia | Metabolism and nutrition disorders | 1 of 3 |
Serious events with the highest arm-level rate: bronchopulmonary hemorrhage (66.7%), hypoxia (66.7%), acidosis (33.3%), hypotension (33.3%), multi-organ failure (33.3%).
The adverse-event group is labeled Regimen 2. The record lists 3 participants at risk for serious adverse events, of whom 2 were affected, and 3 at risk for other adverse events, of whom 3 were affected. It also lists 3 deaths. These are descriptive registry counts; the record does not provide a comparison group or an analysis that attributes events to the transplant or any individual treatment.
The listed serious-event terms include bronchopulmonary hemorrhage and hypoxia, each at 66.7%, and acidosis, hypotension, multi-organ failure, and myelitis, each at 33.3%. The registry record does not explain whether the same participant could contribute to more than one term, whether a term reflects multiple episodes, or the period over which events were collected. The percentages should not be summed or treated as mutually exclusive shares of participants.
The record does not report event timing, severity grading rules, relatedness assessments, or the circumstances of the deaths. The death count should therefore not be assumed to represent treatment-caused deaths, and the adverse-event counts alone do not provide a comparative safety estimate. They describe what was entered in the registry record, with important context and analysis details not reported.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a study of a two-donor, HLA-haploidentical transplant strategy was conducted as a non-randomized, parallel study without masking, and that it enrolled 3 participants before being terminated. It also records adverse-event counts for a group labeled Regimen 2. These registry entries describe the study and its registry entries; they do not provide a complete assessment of transplant outcomes.
The stated primary objective covered several clinically distinct outcomes at 1 year, but the registry record explicitly says the primary objectives could not be analyzed because of small accrual and patient course following treatment. No numerical primary outcome results are reported. It is therefore not possible to quantify the outcomes named in the objective from the record or to assess their precision. No estimate should be interpreted as evidence that the intervention works or does not work.
The adverse-event information warrants similarly careful interpretation. It reports affected counts and percentages for serious-event terms, along with deaths, but does not establish causation, timing, overlap among event terms, or a comparison with another group. These figures are not a standalone estimate of the risk attributable to treatment.
In general, a small study can provide descriptive experience but may be unable to support stable estimates or meaningful comparisons. The record does not report the protocol’s sample-size justification, detailed statistical plan, or analysis populations. Any planning illustrations described in the record are not observed power and are not a substitute for analyzable outcomes. The most defensible reading is that the registry describes the study’s intended question and some safety entries, while leaving the main efficacy question unanswered.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the distance between a clearly stated clinical objective and an analyzable result. The study intended to assess multiple aspects of transplantation, including survival, disease-free survival, engraftment, GVHD, and infection. Yet the registry record reports enrollment of 3 and states that the primary objectives could not be analyzed. Without primary estimates and their uncertainty, neither the magnitude nor precision of outcomes can be evaluated.
The non-randomized design is also important. In general, random allocation helps balance measured and unmeasured participant characteristics across groups, while non-randomized treatment assignment can leave group differences entangled with treatment differences. This record does not identify a suitable randomized comparison, so it cannot establish a causal treatment contrast. The lack of masking may also be relevant to outcome assessment, depending on the outcome, but the record does not describe assessment procedures sufficiently to judge its influence.
The safety entries demonstrate why counts require context. Serious adverse events and deaths are important descriptive observations, but without timing, event attribution, counting rules, or a comparison group, they do not quantify treatment-caused risk. A percentage attached to an event term does not by itself communicate precision or independence among events.
More broadly, planning calculations and observed findings answer different questions. General sample-size illustrations depend on assumptions and do not show that a study had adequate power or that a clinical effect was established. Here, the record’s planning assumptions should not be confused with completed primary analyses. The statistical lesson is not a judgment about the treatment; it is that the registry’s stated objectives cannot be answered with the reported primary results.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The principal limitation is that the registry record says the primary objectives could not be analyzed. Enrollment was 3, and no numerical results are reported for the primary outcomes. The record therefore does not support estimates of survival, disease-free survival, transplant-related mortality, engraftment, graft failure, GVHD, or opportunistic infections.
The non-randomized allocation and absence of masking limit the kinds of comparisons the design can support. The record does not report a suitable control group, detailed allocation procedures, baseline characteristics, or outcome-assessment methods. Any comparison between groups would require caution, and a causal interpretation is not established by the registry entries.
The descriptions of both regimens are incomplete. The record does not fully establish which interventions each participant received, how participants were assigned to the regimen groups, or the treatment exposure received. Although the adverse-event group is labeled Regimen 2, that label cannot resolve these missing treatment details.
Safety interpretation is limited by the absence of reported event timing, relatedness, severity definitions, counting rules, and overlap among the listed event terms. The record lists deaths but does not report their causes or relation to treatment. Follow-up completeness and the handling of missing outcomes are not reported in the registry record.
The registry record also does not report the protocol’s sample-size justification, statistical analysis plan, interim analyses, multiplicity approach, or analysis populations. The stated 1-year timeframe does not establish complete follow-up for every participant. These omissions, together with small accrual and the absence of primary analyses, mean that both efficacy and comparative safety remain undetermined by the posted results.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Biparental HLA Haplotype Disparate T-cell Depleted Transplants for Patients Lacking an HLACompatible Donor — NCT01598025.
- Registry record last updated 2018-08-09; status last verified 2018-07.
- Results first posted 2018-04-17.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
NCT01598025 evaluated a biparental HLA-haploidentical, T-cell depleted CD34+ peripheral blood stem cell transplant strategy for patients lacking an HLA-compatible donor. The registry record describes a non-randomized, parallel study with no masking and a phase recorded as NA. It lists Memorial Sloan Kettering Cancer Center as sponsor, enrollment of 3, and status as terminated. The study start is recorded as 2012-05-02 and primary completion as 2017-10-16.
The primary objective covered several transplant outcomes assessed at 1 year. The registry record states that the primary objectives could not be analyzed because of small accrual and patient course following treatment. Descriptive adverse-event entries are reported for Regimen 2, including serious and other adverse-event counts and 3 deaths; the record does not establish causation. Detailed analysis methods, missing-data handling, and analysis populations are not reported in the registry record.